High Lockout
L8 on Ideal Classic FF

Your boiler has detected a problem with its internal fan or the power supply to it, preventing the unit from starting safely.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

FAN

What causes this fault?

This fault occurs when the boiler's control board detects that the fan is not spinning at the correct speed or has failed to start at all. The most common reason is that the fan motor has seized due to age, or the electrical connection between the motor and the main control board has been interrupted.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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